Java Random Number Generator using a Seed

Question

Possible Duplicate:
Java random always returns the same number when I set the seed?
Java Random Numbers Using a Seed

Hi, This is my code. I am trying to generate 2 random numbers simultaneously using a seed i.e. 15416640. The numbers that are getting generate are not really random.

Random radiusGenerator = new Random(15416640);

Random angleGenerator = new Random(15416640);

try
{
    for(int i=1; i<=sequenceNumber; i++)
    {
        double radius =  (0.5 - (0.5 * Math.sqrt(1-radiusGenerator.nextDouble())));
        double angle = angleGenerator.nextDouble();
        angle = angle*(Math.PI*2);

        System.out.print(radius+"      "+ angle +"\n");
     }

Please Help...Thanks!

and the above duplicate is posted by same user yesterday !!! — mtk, Sep 19 '12 at 08:02
@mtk well seen. OP, tell us if something wasn't clear or still isn't clear, so that you don't have to ask again. — Denys Séguret, Sep 19 '12 at 08:03

score 1 · Answer 1 · answered Sep 19 '12 at 07:58

1

That's totally normal and a feature : in a Pseudo Random Generator, the seed defines the sequence of numbers that will be generated.

answered Sep 19 '12 at 07:58

Denys Séguret

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score 0 · Answer 2 · answered Sep 19 '12 at 07:58

0

Use one Random object, and generate everything you want. Since you initialize 2 Random object with the same seed, they will generate the same number if you call with the same method.

answered Sep 19 '12 at 07:58

nhahtdh

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even if i am using one generator....the numbers are not properly random – Rahul Bhatia Sep 19 '12 at 08:04
@RahulBhatia: Use the seed = current time in milliseconds from Epoch. – nhahtdh Sep 19 '12 at 08:06
@RahulBhatia Please read the answers given to your previous question : both explanation and solution were provided – Denys Séguret Sep 19 '12 at 08:11

Java Random Number Generator using a Seed

2 Answers2